Avoiding The Dreaded Spam Filter

Greg Khaikin

Meet Nikki.

Nikki sends emails.

Nikki enjoys a high deliverability rate on her emails.

Nikki avoids common spammer tactics in her email.

Be like Nikki.

It is not uncommon for an Informz user to ask their Advisor why some of their subscribers haven’t received an email, even when the report is showing that it was delivered. In almost every case the answer is that the message got caught up in the subscriber’s spam filter. That usually leaves our users asking “How did that happen? I’m not a Spammer!”

To understand why your messages may be mistaken for spam, it’s good to understand how spam filters work, what they look for in emails and what you should avoid to keep out of the spam folder.

How Do Spam Filters Work?

Spam filters do their best to identify unwanted messages and keep them from reaching our inboxes, but sometimes they get it wrong and a legitimate message or sender is marked as spam. Spam filters look at several components of your message and assign it a score. Using “spammy” words and phrases like “Free!” or “Save $,” too much punctuation, a subject line in all caps and other common spammer methods will raise that score. Having a strong sender reputation (a history of sending emails that are delivered and not reported as spam) and properly configured SPF and DKIM records will lower that score. If the score is above a certain threshold the message is categorized as spam and never makes it into your subscriber’s inbox. Most spam filters don’t make public exactly what they are looking for since that would make it easier for spammers to circumvent the filter. Fortunately, you’re reading this blog and will know what to do to lower that risk!

Common Spam Triggers

So what should you avoid in your email to keep spam filters happy? The list below is a great place to start. These are things you should avoid when possible. Sneaking one of these into your mailings every once in a while won’t be disastrous, especially if you have a strong sender reputation, but they should be used sparingly!

  • Avoid words or entire subject lines in ALL CAPS.
  • Don’t use one word subject lines.
  • Be sure to include a working unsubscribe link.
  • Don’t try to trick your subscribers by putting “re:” at the beginning of your subject line.
  • Avoid excessive punctuation!!!
  • Don’t send emails that are just images.
  • Don’t use the URL as the text for your hyperlink.
  • Avoid spam trigger words, especially in your subject line.

Spam Trigger Words

There’s no definitive list and what spam filters look for is always evolving. Using these words and phrases sparingly can be okay. For example, you’ll notice the word “free” several times on this list, but it is also recognized as a word found in some of the best performing subject lines. A good rule of thumb is to think about what the emails that wind up in your own junk folder look like, and keep that in mind when creating your emails.

Below is a partial list of words and phrases to avoid:

100% satisfied
Accept credit cards
Act Now!
Additional Income
All natural
All new
Apply online
Best price
Billing address
Buy direct
Call free
Can’t live without
Cards Accepted
Cents on the dollar
Click / Click Here / Click Below
Click to remove
Compare rates
Cost / No cost
Dear friend
Do it today
Extra income
For free
Free and FREE
Free installation
Free leads
Free membership
Free offer
Free preview
Free website
Full refund
Get it now
Giving away
Increase sales
Increase traffic
Information you requested
Investment / no investment
Investment decision
Marketing solutions
Message contains
Month trial offer
Name brand
No gimmicks
No Hidden Costs
One time / one-time
Order / Order Now / Order today / Order status
Orders shipped by priority mail
Please read
Potential earnings
Print out and fax
Real thing
Removal instructions
Risk free
Satisfaction guaranteed
Save $
Save up to
Search engines
See for yourself
Serious cash
Special promotion
The following form
US dollars
Work at home


Ready for more tips to make sure your emails make it to your subscriber’s inbox? Check out more deliverability blog posts here.

About the Author
Greg Khaikin

As the Informz West Coast Advisor, Greg works with his clients to make their digital marketing the best it can be. When not in the office you can find him at the local multiplex or doting on his dog, Dudley.